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9,10-Phenanthrenequinone (9,10-PQ) is one of the most abundant quinones among diesel exhaust particulates. Recent data have suggested that quinones induce apoptosis in immune, epithelial and tumor cells, leading to respirator illness; however, the mechanisms by which quinones induce apoptosis and the structure required for this remain unknown. We studied the antitumor activity of 9,10-PQ analogs against two human tumor cell lines, HCT-116 colon tumor cells and HL-60 promyelocytic leukemia cells. The loss of the cis-orthoquinone unit in 9,10-PQ abrogated its ability to induce apoptosis in the two tumor cell lines, and the LC50 values of these analogs were indicated over 10 μM. An analog of 9,10-PQ in which the biaryl unit had been deleted displayed a reduced ability to induce tumor cell apoptosis, while the analogs 1,10-phenanthroline-5,6-dione (9) and pyrene-4,5-dione (10), which also had modified biaryl units, exhibited increased tumor cell apoptotic activity. The cis-orthoquinone unit in 9,10-PQ was identified as essential for its ability to induce apoptosis in tumor cells, and its biaryl unit is also considered to influence orthoquinone-mediated apoptotic activity.  相似文献   
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Summary By indirect immunofluorescence microscopy, the reactivities of extra- and intrafusal muscle fibers with antibodies against troponin (TN) components were studied in an avian slow muscle, the anterior latissimus dorsi (ALD) of the chicken. Serial cross sections of the muscle were exposed to antibodies specific to TN components (TN-T, -I, and -C) from adult chicken breast and ventricular muscles. In extrafusal fibers, four distinct categories were identified on the basis of differential reactivity with these antibodies. The predominant population of fibers (> 95%) reacted weakly only with antiventricular TN-C. The second type of fibers (< 5%) was stained with antibodies raised against breast TN components. The third group of fibers (< 1%) was labeled not only with antibreast TN components, but also with antiventricular TN-T and -C. The last class of fibers (< 1%) reacted with antibodies directed against ventricular TN-T and -C. These results were correlated with myofibrillar ATPase staining patterns of fibers. In intrafusal muscle fibers of this muscle, the same four types of fibers were observed; in these fibers, however, there appeared to be a longitudinal variation in the reactivity. In conclusion, the slow ALD muscle of the adult chicken contains populations of both extrafusal and intrafusal fibers which are heterogeneous in reactivity with TN component antibodies.  相似文献   
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Rat physiologic urinary proteins were immunohistochemically localized. In male Wistar rats, urinary protein antigens were present in both hepatic and epithelial cells of the salivary ducts, the coagulating gland, and the prostate gland. In female rats, urinary protein antigens were present in the same proportion of the salivary glands as in males and in the uterine glands, but to a lesser extent than in salivary glands. The results of this study indicate multiple origins of rat urinary proteins. It remains to be determined if female uterine glands contribute to urinary proteins.  相似文献   
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The distribution of ent-2,3-secoaromadendrane-, ent-aromadendrane-, ent-bicyclogermacrane- and ent-maaliane-type sesquiterpenoids in fourteen Plagiochila species is described. These sesquiterpenes are the significant chemosystematic markers of Plagiochila. The intense pungent substance of some Plagiochila species is due to an ent-2,3-secoaromadendrane-type sesquiterpene hemiacetal, plagiochiline A.  相似文献   
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Three new pinguisane-type sesquiterpenes, dehydropinguisanin, dehydropinguisenol and pinguisenal together with the previously known deoxopinguisone, pinguisanin, pinguisanolide and (—)-bicyclogermacrene, have been isolated from the liverwort, Trocholejeunea sandvicensis, and their structures have been established from spectral evidence.  相似文献   
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Three liverworts, Trichocolea tomentella, Neotrichocolea bissethii and Trichocoleopsis sacculata belonging to Jungermanniales were chemically investigated. Isoprenyl benzoates are the important chemical markers of Trichocolea tomentella. Neotrichocolea bissethii elaborates sesquiterpenes as the major components. The sacculatane-type diterpenes and pinguisane-type sesquiterpenes are the significant chemosystematic markers of Trichocoleopsis sacculata. These three species are chemically quite different. Trichocoleopsis sacculata is chemically rather close to Porella species. The present chemical results support the recent morphological classification of the above three species proposed by Schuster. Some species of Jungermanniales are chemically identical to those of Metzgeriales and these results also support the phylogenetic classification in which the two orders have been united within the subclass Jungermanniae.  相似文献   
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